Sources

- http://education.jlab.org/itselemental/ele028.html

- http://.webelements.com/webelements/elements/text/Ni/key.html

- http://www.enia.org/index.cfm/ci_id/14305/la_id/1.htm%3E%3Cimg%20src=

- http://www.lenntech.com/Periodic-chart-elements/Ni-en.htm

Pictures:

- http://www.webelements.com/webelements/elements/text/Ni/pics.html